Pulp-agitating apparatus.



W. G. PATERSON.

PULP AGITATING APPARATUS. APPLIGATION FILED SEPT. 13, 1910.

2 SHEETS-SHEET 2.

QWL lzgyliwa to? Patented Aug. 15, 1911.

'To all whom it may concern: I

WILLIAM CAMPBELL IATERSON, 01 DENVER, COLORADO.

PULP-AGITATING- APPARATUS.

Specification of Letters Patent. Patented Aug. 15, I911.

Application filed September 13, 1910. Serial N 0. 581,920.

' and to the figures of reference marked.

thereon, which form apart of this specification. Y

My invention relates to improvements in pulp agitating apparatus, and may be employed for agitating pulp of any character, although itis particularly adapted for use 'inthe agitation and aeration of pulp composed of pulverized ore and the necessary solution for dissolving its metallic values; and to be still more specific, the special object which I have in mind is the treatment of pulp formed from pulverized ore and a solution of cyanide of potassium, for the purpose of facilitating the dissolving of the metallic "alues through the action of the chemicals.

My improved construction is adapted to thoroughly agitate and aerate the pulp, whereby the precious metals to be dissolved are more advantageously subjected to the action of the dissolving chemicals, thus greatly shortening the time during which it is'neoessary for the ore to remain in 'contact with the solution.

Provision is made in my improved construction for the employment of either a single tank or unit, or a series of tanks.

- Where a series of tanks is employed, the

pulp is passed through a solution of the various tanks successively, the number of tanks being such that the solution may be continuously drawn from the last tank of the series, since during the passage ofthe pulp through the various tanks sufiicient time has elapsed, in view of the advanta geous conditions under which the pulp is handled, to thoroughly dissolve or place in solution the metallic values. When, however, a single tank or unit only is employed, the ore particles are kept in the tank and subjected to the action of the dissolving chemicals as long as may be necessary for the purpose. In my improved agitating apparatus provision is'also made for drawing off the solution from each initial tank in a practically clear state, wherebyit becomes -practicalgle to pass the same through a rotary pump without injury-to the latter, the pump belng the power employed to deliver the solution to the tank for agitating pur- I poses.

In the construct-ions heretofore employed,

it has been impracticable to employ a rotary.

pump for handling pulp of this character,

for the reason that the ore particles are drawn into the pump and soon destroy the same. 'However, in my improved apparatus, I equip the conduit through which the solution is' drawn from the tank for agitating purposes, with a flexible member inside the tank, the latter having a float at its free extremity, of such buoyancy as to maintain the receiving end of the inlet end of the conduit close to the top of the solution within the tank, this inlet end of the conduit being located in an annular compartment which is separated by a cylindrical partition from the portion ofthe tank containing the liquid, which is in a constant state of agitation. Hence by virtue of the fact that the liquid within the draw-oil compartment is practically quiet, I am enabled to draw 01f practically pure solution,

or solution which is practically free from F ore particles, notwithstanding the contents In this drawing: Figure 1 is a central vertioal' section taken through my improved "agitating apparatus, complete in a single tank or un1t. Fig. 2 is a similar section showing a plurality of tanks connected to be employed as a battery, whereby the pulp is passed successively from one tank to the \Vith the bottom of the tank as provided,

which is open for the purpose, is connected an outlet pipe 9 controlled by a valve 10. This outlet pipe is utilized for drawing oil or removing the solid matter from the tank after the metallic values have been dissolved and the solution removed.

Mounted centrally within the tank and open at both ends, is a stand-pipe 12, whose lower extremity is outwardly flared as shown at 13, the channel of the pipe above this flare being equipped with a bushing 14, whereby the diameter of the pipe is reduced as shown at 15 for injection purposes. The upper portion of this stand-pipe is surrounded by a cylindrical partition 16, open at both ends,

and whose upper extremity is inwardly flared as shown at 17 This partition is sup-- ported upon the body of the tank by means of angle brackets 18, or in any othersuitable manner. The upper extrem ty of the pipe 12 terminates a short distance below the flared portion 17 of the partition; while located directly above the top of this pipe and projecting into the upper portion of the compartment inclosed by the partition 16, is a sort of battle plate 19, which is connected with a stem 20 threaded into an opening 21 formed in a cross piece 22 with which the top of the tank is provided. The object of this baflle plate is to prevent the pulp and solution, as it is forced up through the pipe 12 and out at the top' thereof, from being thrown beyond the flared top of the partition. In this way the liquid in the annular compartment 23 between the partition and the wall of the tank, is maintained in a practically quiet state. It is preferred that the bafile plate or disk 19 should have a facing 24,015 rubber, since it has been found in practice that this material gives most excellent results. The upper extremity of the threaded stem 20, located outside. of the tank} is provided with a hand wheel 25 to facilitateits adjustment. If desired, this baflle platemay be adjusted to completely close the up per extremity of the stand-pipe 12, whereby the solution may be forced upwardly into the said pipe and caused to escape at its lower extremity, in case the latter'should become clogged.

T he pulp to be treated, in the form of pulverized ore mixed with the proper solution of cyanid of potassium, may be fed into'the central compartment 26 of the tank, from a spout 27-, properly arranged for the purpose, or in any other suitable manner. The solution within the tank 5 is drawn ofi' for agitating purposes through an elbow 28 which protrudes into the annular compartment 23 of the 'tank. lVith this elbow is connected a flexible hose pipe member 29, whose upper extremity is equippedwith a float 30 of such buoyancy as to maintain the inlet extremity of the hose pipe a short distance below the level of the liquid in the compartment. By virtue of this arrangement any scum or other substance floating and maintained on the upper surface of the liquid will be prevented from entering the pipe, while at the same time the inlet extremity of the pipe will be held at a sufficient elevationto prevent the entrance of ore particles or solid material of any kind. By virtue of this construction and arrangement, practically only clear solution isdrawn ofl through the elbow 28. This elbow is connected outside of the tank with a down pipe 31 leading to arotary pump 32, having an outlet member 33 passing through the casing 7 and communicating by means of an elbow 3 1 with an upwardly-extending pipe member 35, provided with a valve 36. The upper extremity of the pipe 35 is connected by means of an elbow 37 with a horizontally arranged pipe member 38, which passes through the cone-shaped bottom 6 of the tank, its inner extremity being equipped with an upwardly directed cone-shaped nozzle 39, which .enters the outwardly flared lower extremity of the stand-pipe 26 within the tank.

Extending upwardly from the upper extremity of the down pipe 31 is a relatively small air pipe 10, whose upper extremity extends above the top of the tank, and consequently above the possible level of the liquid therein. The upper portion of this air pipe is equipped with a controlling valve 41. The apparatus is further provided with an outlet pipe 42 for removing the solution from the tank, or through which the pulp may pass to the next tank when a series or battery of tanks'is employed. The lnner extremity of this outlet pipe 42 is equipped ing provided with a float 45 of such buoyancy' as to maintain the" inlet extremity of the hose pipe a short distance below the level of the liquid in the inner compartment 26.

In Fig. 1 the liquid level in the compart-- ment 26 is indicated by thedotted line 46. Where the apparatus is employed as a rap unit as shown in Fig. 1 practically clear solution will be drawn 0 through the pipe 44, though the solution is taken from the central compartment 26 of the agitating tank, since before the solution is drawn off, the agitating operation will cease for a sufficient length of time to allow the solid particles of matter to settle in the bottom of the tank. When, however, a battery of tanks is employed, the agitationcontinues while the pulp is discharged from the initial tank to the next tank, and so on successively through the entire battery, since in this case it is necessary to carry the ore particles through all of the tanks, whereby they may be sub ected to the solution of the various tanks, for the necessary period.

When the apparatus is in use as a unit (see Fig. 1), it may be assumed that the tank is filled to the level indicated by dotted lines, with a pulp of suitable consistency and composed of ore pulverized to the desired fineness to release the metallic values, and a solution of cyanid of potassium of the desired strength. The rotary pump '32 is then put in operation. It is assumed in this case that-the valve 41 of the air pipe and the valve 36 of the tank inlet pipe 35 are both open, also that the valve 47"is closed, with which the exteriorly located portion 48 of the discharge pipe 42 is equipped. In

, this event the pump 32 withdraws the solution from the upper portion of the annular compartment 23 of the tank, in a practically clear state, and forces it through the nozzle 39 upwardly into the bottom of the standpipe 12, whereby an upward current is produced within the said pipe, causing the solution to be drawn into the bottom of the pipe on the injector principle. .Under these circumstances the liquid is continuouslycirculated upwardly through the pipe 12 passing out at the top thereof and-returning to the body of liquid in the top of the tank, which is continually passing downwardly outside of the pipe, whereby a most advantageous circulation of the pulp is obtained for agitating purposes. At the same time the contents of the tank are aerated by virtue of the air drawn thereinto through the pipe 40. After the agitation of the pulp has been continued for the required period, the pump will be stopped, and the valves 41 and 36 closed. The solid particles of matter will then be allowed to settle in the bottom of the tank, after which the solution will be drawn off through the pipe 42, the valve 47 being opened for the purpose. It will be understood that as the level of the solution lowers within the tank, the float 45 connected with the flexible conduit 44 will also fall and constantly maintain approximately the same position with reference to the'level of the solution. After the solution has been removed from the tank and the solid matter or ore particles have been through the casing 7 of the adjacent tank,

and enters the conical bottom 6, where it discharges as shown at 50. In this manner the pulp passes freely from one tank into another, and after having passed through all the tanks, is deprived of its metallic values, which have been dissolved by the chemicals. Hence this solution may be continuously drawn from the last tank of the battery or series, while the pulp may be constantly fed into the top of the initial tank of the series. Under these circumstances the feeding into the initial tank and the discharge from the last tank should be I so regulated as to practically balame each other, whereby a practically uniform depth of solution is maintained in all the tanks of the series or battery.

It will be understood that the-agitation of the pulp in the individual tanks of the battery of'tanks, is accomplished in precisely the same manner as where only a single tank or unit is employed.

The element 19 which has been heretofore designated .as a bafile plate or disk, also serves to distribute the pulp in a thin sheet around the top of the pipe and not only prevents the pulp from being thrown into the top of the annular chamber 23, but also serves to produce further and advantageous aeration of the pulp. By closing the top of the standpipe 12 by the baffle plate, the taking of solution from the annular chamber 23 is attended by the drawing of a greater quantity of air through the pipe 40 and. a consequent introduction of the same intothe pulp, whereby further aeration is obtained. This is apparently due to the nation of a tank having a centrally located open-ended stand-pipe, an annular partition supported in the upper portion of the tank, surrounding the stand-pipe and forming an annular chamber between the said partition and the wall of ,the tank, and means for drawing off solution from the said annular chamber and discharging it &

into the lower extremity of the stand-pipe,

from the said annular com artment, re-

turning it to the tank and ischarging it into the lower extremity of the stand-pipe under pressure, said means including a flexible member located within the said annular compartment and equipped with a float, for the purpose set forth.

3. In an apparatus of the class described, the combination of a tank having a conical bottom, an open-ended stand-pipe supported within the tank, the lower extremity of the stand-pipe being located in the lower portion thereof and having free communication with the contents of the tank, a partition located in the upper portion of the tank, surrounding the stand-pipe and forming a compartment between the partition and the wall of the tank, and means for drawing ofl' solution from the upper portion of the annular compartment and discharging it into the lower extremity of the stand-pipe, said means including a flexible conduit member located in the said compartment between the partition and the wall of the tank, its upper extremity being equipped with a float, for the purpose set forth.

4. In an apparatus of the class described, the combination of a tank, an open-ended stand-pipe centrally located in the tank, a

partition supported in the upper portion of I the tank, surrounding the stand-pipe and forming an annular chamber between the partition and the wall of the tank, and means for taking the solution from the annular compartment of the tank, returning it to the tank and discharging it into the lower extremity of the stand-pipe, said means 1ncluding a rotary pump, and a flexible conduit member located in the said annular chamber and having afloat attached to its upper extremity for maintaining it just below the level of the liquid in the compartment, for the'purpose set forth.

5.1In an-apparatu's'of the class described,

,. the combination of a tank having a centrally located open-ended standpipe in communication with the contents of'thetank, an open-ended cylindrical partition supported in -the upper portion of the tank and forming'an annular chamber betweenthe partition and the wall of the tank, means for drawing oif solution from the annular chamber and introducing it into the lower extremity of the standpipe including a conduit located within the annular chamber, the upper extremity of the cylindrical partition being upwardly flared, and a bafiie plate mounted directly above the upper extremity of the stand-pipe, for the purpose set forth.

6. In an apparatus of the class described, the combination of a pulp-containing tank, having an open-ended stand-pipe supported therein, the lower end of the pipe belng in communication with the pulp in the tank, an annular partition sup orted in the upper portion of the tank and orming an annular chamber between the said partition and the wall of the tank, means for drawing off solution from the said annular chamber and introducing it into the lower extremity of the stand-pipe, and means for drawing ofl solution from the inner compartment formed by the said partition, substantially as described.

7. In an agitating apparatus of the class described, the combination of a pulp-containin'g tank having an annular partition supported in its upper portion, forming an annular chamber between the said partition and the wall of the tank, and means for drawing ofi' solution from the annular chamber of the tank and discharging it into the lower portion of the same tankincluding a conduit located within the annular chamber, for the purpose set forth.

-8. In an agitating apparatus of the class described, the combination of a tank having a conical bottom, an open-ended stand-pipe centrally located in the tank, an annular partition supported in the upper art of the tank, surrounding the said stan -pipe and forming an annular chamber between the partition and the wall of the tank, a flexible conduit located within the said annular chamber and equipped with a float, the said conduit leading from the said annular chamber, extending outside the tank, and returning to the lower portion thereof for discharging the solutionto the lower extremity of the stand-pipe, an air pipe communicating with the said conduit for purposes of aeration, and a pump connected in operative relation with the conduit, whereby the pulp is delivered to the tank under suitable pres-' sure, for agitating purposes, substant ally tion from the compartment within the antanks may be kept aplpggximately uniform,

nular partition of each tank except the last, substantially as descri 10 and discharging it into the adjacent tank, In testimony whereof I aflix my signature the initial tank being equipped with means in presence of two witnesses.

for feeding the material to be treated to the WILLIAM CAMPBELL PATERSON. tank, and the last tank being equipped with Witnesses: means for continuously drawing ofi' solu- A. J. OBRIEN,

tion', whereby the level of the pulpin all the F. BOWEN. 

